KeyShot Forum

Technical discussions => Rendering => Topic started by: sevenlo on January 07, 2014, 05:14:40 PM

Title: Triangle problems
Post by: sevenlo on January 07, 2014, 05:14:40 PM
Hello everyone, I keep on encountering this problem when rendering this same model that I have made. Triangles appear at the ceiling every time. I checked my model in rhino if there were any overlapping surfaces but there were none. I imported the model to keyshot using the plugin that lets rhino files to be directly imported to keyshot. Please help. I need to finish this render before Thursday :(
Title: Re: Triangle problems
Post by: NDenekamp on January 07, 2014, 08:46:08 PM
It's hard to say..

- Were these these little spots of triangle meshes appearing from the the start, or only revealed themselves after applying materials / lights? If so does applying a different material reduce / remove the issue?
- Is the light falling in through the ceiling the HDRI or a modelled light plane? in either case is there any geometry on the outside of you model or just this ceiling plane?
- Have you tried remodelling this part of the ceiling geometry again in Rhino (i.e. removing the planar surface from the object and using the Cap command to bring it back)
- If all else fails is it feasible to remove the offending triangles in retouching, or are there too many views to be rendered?

n
Title: Re: Triangle problems
Post by: KeyShot on January 07, 2014, 11:07:24 PM
You can explore the underlying triangle mesh using the wireframe material. If you can share the model with support@luxion.com then we can take a look at it as well. It could also be related to the normals being wrong for those few triangles.
Title: Re: Triangle problems
Post by: sevenlo on January 08, 2014, 03:09:18 AM
Remodelling the part with spots of triangle worked! Thank you so much guys! :D This problem has also occurred in some of my past renders. Can you guys give me some advice on how I can avoid these spots of triangle? And what causes these triangles to appear in the first place?
Title: Re: Triangle problems
Post by: gabrielefx on January 19, 2014, 11:53:44 PM
I notice this behaviour importing some models from Max.
Meshes with few triangles are not well smoothed and in Keyshot I don't find a command to shade them flat or smooth.
In 3ds Max exists a modifier called "smooth" that interpolates meshed build with few polygons. It works on shading, is not a mesh smoother, it doesn't add new triangles.
This modifier doesn't help the geometry, it's rendered in Keyshot with weird shading.
Any trick?

regards
Title: Re: Triangle problems
Post by: thomasteger on January 20, 2014, 06:06:42 AM
Correct - we don't do any smoothing. You will need to make sure that you increase the polygon count in Max.